Courmisch

A1. Finnair only has business (and economy) anyway.

A2. As previous posters said, practically all intra-European flights nowadays on any carrier offer identical seats to business and economy class customers - though the middle seat is blocked in business. Thus if you absolutely want a better seat for the entire journey, you need to book an itinerary with a segment direct from Asia orthe Middle East to your final destination. Needless to say, that won't be possible with Finnair to Berlin.

In fact, there are very very such options to Berlin presumably because of congestion pending the opening of Brandenburg airport. The only ones I could find where Hainan (via Beijing) and Etihad (via Abu Dhabi).

A3. I flew QF5 (SYD->SIN) recently with transfer to Finnair afterwards. That flight most definitely has a real business class section - though I was in Y meeself.